104 lines
5.8 KiB
Markdown
104 lines
5.8 KiB
Markdown
---
|
|
type: api
|
|
title: Config Schema
|
|
description: Required/optional environment variables, validation rules, and the typed Config dataclass returned by tenbackward.config.load_config.
|
|
tags: [config, env, schema]
|
|
timestamp: 2026-08-04T17:51:00Z
|
|
---
|
|
|
|
# Purpose
|
|
|
|
`tenbackward.config.load_config()` is the single boundary that turns
|
|
process environment + optional `.env` file into a typed `Config`
|
|
dataclass. Job 1083 changes every variable that ships in
|
|
`.env.example` so that it is **explicitly required** at every layer
|
|
(`entrypoint.sh`, `config.validate_config`, and the rendered cron).
|
|
|
|
# Required Environment Variables
|
|
|
|
All eight of these must be present and non-empty in the process
|
|
environment for the container to boot.
|
|
|
|
| Key | Purpose | Validation |
|
|
|----------------------|--------------------------------------------------------|------------------------------------------------------------------|
|
|
| `MASTODON_BASE_URL` | Mastodon instance to post against. | Must parse with `http` or `https` scheme and a non-empty netloc. |
|
|
| `MASTODON_ACCESS_TOKEN` | OAuth token used by the future Mastodon.py client. | Required string. |
|
|
| `VISIBILITY` | Default post visibility. | Must be `public` or `unlisted`. |
|
|
| `SITE_URL` | Source blog URL (used by the future clone step). | Must parse with `http` or `https` scheme and a non-empty netloc. |
|
|
| `HASHTAGS` | Comma-separated hashtags appended to every throwback. | Required string (formatting handled by the future poster). |
|
|
| `THROWNBACK_PREFIX` | Per-post title prefix (default: `Throwback:`). | Required string. |
|
|
| `MAX_RETRIES` | Number of additional retries after the first attempt. | Non-negative integer (parsed by `_parse_max_retries`). |
|
|
| `RUN_AT` | Daily fire time for the cron entry. | `HH:MM` 24-hour format. |
|
|
| `TZ` | IANA timezone used by cron + the container clock. | Must resolve via `zoneinfo.ZoneInfo`. |
|
|
|
|
> **Note** — All nine keys are required since Job 1083. The previously
|
|
> optional `MASTODON_VISIBILITY`, `THROWBACK_PREFIX`, and `RETRY_COUNT`
|
|
> were promoted to first-class citizens and renamed to `VISIBILITY`,
|
|
> `THROWNBACK_PREFIX`, and `MAX_RETRIES`.
|
|
|
|
# Defaults
|
|
|
|
`DEFAULTS` in `config.py` provides fallback strings that `apply_defaults`
|
|
fills into the merged map **before** validation runs:
|
|
|
|
| Default key | Default value |
|
|
|-----------------------|-------------------|
|
|
| `VISIBILITY` | `public` |
|
|
| `THROWNBACK_PREFIX` | `Throwback:` |
|
|
| `MAX_RETRIES` | `3` |
|
|
| `TZ` | `Europe/Berlin` |
|
|
| `RUN_AT` | `09:00` |
|
|
|
|
Because every required key carries a default, a freshly-initialised
|
|
container can still boot to validate the scaffold, but the operator
|
|
must supply `MASTODON_BASE_URL` and `MASTODON_ACCESS_TOKEN` (and
|
|
ideally `SITE_URL`) to make a real run.
|
|
|
|
# `Config` Dataclass
|
|
|
|
| Field | Type | Source |
|
|
|-------------------------|-----------|----------------------------------------------|
|
|
| `mastodon_base_url` | `str` | `MASTODON_BASE_URL` |
|
|
| `mastodon_access_token` | `str` | `MASTODON_ACCESS_TOKEN` |
|
|
| `visibility` | `str` | `VISIBILITY` |
|
|
| `site_url` | `str` | `SITE_URL` |
|
|
| `hashtags` | `str` | `HASHTAGS` |
|
|
| `throwback_prefix` | `str` | `THROWNBACK_PREFIX` |
|
|
| `max_retries` | `int` | `MAX_RETRIES` (parsed as non-negative int) |
|
|
| `run_at` | `str` | `RUN_AT` |
|
|
| `tz` | `str` | `TZ` |
|
|
| `data_dir` | `Path` | Constant: `Path("/app/data")` |
|
|
|
|
# Validation Behaviour
|
|
|
|
`validate_config(values)` collects all failures before raising so the
|
|
operator sees every problem at once. A single `ConfigError` lists each
|
|
problem joined with `"; "`. Validation covers:
|
|
|
|
* Required keys are non-empty.
|
|
* `RUN_AT` parses as `HH:MM`.
|
|
* `MASTODON_BASE_URL` and `SITE_URL` parse via `urllib.parse.urlparse`
|
|
with an `http`/`https` scheme and a non-empty `netloc`.
|
|
* `VISIBILITY` is one of `{"public", "unlisted"}` (`ALLOWED_VISIBILITY`).
|
|
* `TZ` resolves via `zoneinfo.ZoneInfo`.
|
|
* `MAX_RETRIES` parses as a non-negative integer (rejects bools).
|
|
|
|
# Exit Codes
|
|
|
|
| Code | Source | Meaning |
|
|
|------|-----------------------------------------|----------------------------------------------------------------------|
|
|
| `1` | `main.main()` (retry budget exhausted) | Pipeline failed on every attempt after `MAX_RETRIES + 1` tries. |
|
|
| `2` | `main.main()` (`ConfigError`) | Configuration was present but invalid; details are logged. |
|
|
|
|
# Citations
|
|
|
|
* [1] `src/tenbackward/config.py` — `REQUIRED_KEYS`, `DEFAULTS`, `ALLOWED_VISIBILITY`, `Config`, `load_config`, `validate_config`.
|
|
* [2] `.env.example` — canonical env-var list.
|
|
* [3] `entrypoint.sh` — shell-side mirror of the required keys.
|
|
|
|
# Related
|
|
|
|
* [System Architecture](/architecture/system-overview.md)
|
|
* [Logging & Run Summary](/architecture/logging.md)
|
|
* [Environment Variable Setup](/operations/environment-setup.md)
|